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Annual Report 2016
SAMCoT
Barents Sea Ice in Waves experiment
The idea of the experiment coordinated by postdoc
Andrei Tsarau was to measure simultaneously the
motions of several ice floes in the field to study the
process of wave attenuation in ice. The heave motion
amplitudes registered by Inertial Measurement Units
IMUs deployed on the ice were used to interpret the
wave amplitude. The wave attenuation coefficient
obtained from the comparison of the wave amplitudes
at two different locations was significantly lower than
the attenuation coefficients reported from previous field
experiments performed in the same area in 1990. This is
most likely due to the much thinner ice observed during
this study compared with 1990.
In April/May 2016 Andrei Tsarau, Aleksey Shestov and Sveinung Løset conducted an experiment in the
Barents Sea Marginal Ice Zone (MIZ). One of the most challenging tasks during this experiment was to deploy,
track and retrieve the equipment to and from small ice floes in high waves. Deploying sensors in the Barents Sea MIZ
Experimental Ice in Waves
campaign at HSVA
Another experimental campaign led by Tsarau was
accomplished at The Hamburg Ship Model Basin (HSVA)
in October/November 2016 during the Hydralab+
Transnational Access project: Loads on Structure and
Waves in Ice (LS-WICE). There were three parts to
this investigation: ice fracture under wave actions;
wave attenuation/dispersion in broken ice covers and
ice-structure interactions under wave conditions. The
experiments confirmed the hypothesis that floe size
strongly affects wave dispersion. It was also remarkable
that in the break-up test the first crack appeared
approximately in the middle of the ice cover, contrary
to the expectation that progressive breaking would be
observed starting from the ice edge. The first crack also
had a profound influence on the subsequent develop-
ment of fractures.
Cutting a continuous ice sheet into uniform size floes at HSVA during the LS-WICE project. Physical and
mechanical properties were measured in the Large Ice Model Basin (LIMB) before a range of waves was
passed through to obtain the attenuation/dispersion relation. Wave measurements were monitored with
pressure transducers and ultrasound sensors.
ICE IN WAVES